I. Field of the Invention
Embodiments of this invention are directed generally to membrane purification processes and apparatus. More particularly aspects are directed to processes and apparatus that reduce bio-fouling of a membrane.
II. Background
Membrane bio-fouling is a major and inherent problem in a variety of filtering processes, such as reverse osmosis seawater desalination. Bio-fouling occurs when the membrane face becomes conditioned with macro-organic compounds and ultimately bacteria attach to the membrane in clusters that become a film of variable thickness. A thin layer of biofilm reduces the efficiency of water flux passing through the membrane and requires it to be cleaned periodically. The cleaning process reduces plant operational efficiency and reduces the life expectancy of the membranes.
Methods of biofouling prevention suggested in the art include devices that involve evaluation of biofilm formation and cleaning using microwaves, vibration, or gas-generated pulses. Additional methods and apparatus are still needed to improve the longevity and efficacy of membranes, particularly membranes used in reverse osmosis methods and apparatus.